Protesters stormed onto the grounds of the Egyptian presidential palace Tuesday in a dramatic escalation of the crisis over President Mohammed Morsi’s decision to give himself absolute judicial power and set a quick referendum on a controversial new constitution.

Police made what appeared to be halfhearted efforts to confront the protesters, who commandeered a police vehicle as they approached the palace and painted graffiti on the palace walls. The inability, or unwillingness, of the police to keep Morsi opponents at bay raised questions about whether the nation’s last remaining arbiter, the military, would intervene in the dispute, and if so, on whose side.

Demonstrations also erupted in other parts of the country. In Alexandria, Egypt’s second largest city, protesters also stormed a presidential palace. In some areas, they vowed to stay the night.

Protesters gathered, as well, in front of the state building in Cairo that houses the government news service, where they beat drums, waved Egyptian flags and called for Morsi to go. “We won’t leave. He will leave,” the protesters chanted, recalling the 18 days of protests early last year that ended in the resignation of then-President Hosni Mubarak. Rusted barbed wire that had been laid out during the anti-Mubarak protests still ringed the building Tuesday.

The turn of events made it appear increasingly difficult for Morsi to ignore his opponents, who charge that the president, a top leader of the Muslim Brotherhood until his election in June, is grabbing power and manipulating events to empower the Brotherhood.

Opponents have said they want a president who’s more representative of the electorate and have demanded that Morsi rescind his declaration of immunity from judicial oversight. They also want him to cancel the constitutional referendum, set for Dec. 15, until a more representative constitutional assembly can produce a document. The current assembly is dominated by the Brotherhood after secular and Christian members withdrew.

In a televised interview late last week, Morsi said the proposed constitution would bring stability. But Tuesday’s protesters said that by pushing a document written by the Muslim Brotherhood-dominated constitutional assembly and rushing a referendum over the objections of some judges, Egypt was entering a period of persistent instability.

The constant threat of protests has paralyzed the capital, with Cairo’s bustling streets routinely empty on protest days.

Morsi also postponed until February a trip to Washington that had been planned for December, but his spokesman, Yasser Ali, denied that the delay was related to the protests.

The demonstration at the palace was one of two that opponents had scheduled Tuesday in Cairo. The other was in Tahrir Square, the epicenter of the anti-Mubarak protests nearly two years ago. At both protests, the crowds chanted “Leave!” and “Down, down with Morsi Mubarak.”

While the protests at Tahrir were relatively subdued, the crowds at the palace began taking down the barbed wire that had been strung Tuesday morning on the road leading to the palace. Police standing behind the wire fired a few rounds of tear gas in an effort to discourage the crowd, but before long they could be seen joking with the protesters. At times, it appeared that some officers had joined in.

“We cannot stop the will of the people,” one officer told a McClatchy reporter, a line eerily similar to what some police officers had said during the anti-Mubarak protests.

Along with police shields, belts and other equipment, protesters nabbed a police truck and began driving it through the crowds. The Reuters news agency, citing unnamed sources, reported that Morsi left the premises as the truck made its way toward the palace, although it wasn’t clear why or where he was headed.

Protesters remained outside the fence that surrounds the palace and its grounds through the evening.

Until the palace protest, it had appeared that the crisis was easing and Morsi had the upper hand. Judges who’d gone on strike had announced that they’d return to work to oversee the referendum. Whether they’d return had been a crucial question that bedeviled plans for the vote on the constitution.

Even at the palace, protesters conceded that they were far less organized than the Brotherhood, which had honed its political rallying skills during over 84 years, during much of which time the group was illegal.

Opponents can’t agree on which politician should lead them: Hamdeen Sabahi, who came in third place in the first round of the presidential election; former Arab League Secretary-General Amr Mousa, who also ran for the presidency; or Mohamed ElBaradei, a former director of the International Atomic Energy Agency.

“Things are escalating to the point we want him to leave. We reject his legitimacy,” said Sandy Rashad, 45, who works in public relations. “I think things will escalate to civil disobedience. It worries everyone. This will go on for some time.”

The controversy was triggered last month, when Morsi issued a seven-point declaration that exempted his decrees from judicial oversight. His supporters said the declaration was necessary to prevent Mubarak appointees to the court from thwarting constitutional reform. But opponents called it a power grab and an attempt to circumvent rulings challenging the legality of the constitutional assembly.

The Supreme Constitutional Court on Sunday postponed a ruling on the issue indefinitely.